In a rally described as a “turning point” on the abortion issue, hundreds of thousands of pro-life supporters, most of whom were college age or younger, marched Friday for an end to abortion in the U.S.

“I think people just don’t realize how pro-life young adults are now,” said Ariana Scecchitano, 21, who came with 400 fellow students from Franciscan University of Steubenville in Ohio.

More than a third of current students’ generation was aborted, said Rueben Verastigui, 19, of the San Antonio Coalition for Life, while addressing the rally on the Mall.

“We will not be silenced,” he said. “I believe we are the chosen generation” that will abolish abortion and change history.

The March for Life has been held every year since the first anniversary of the 1973 Roe v. Wade ruling that created the constitutional right to abortion in the U.S.

Last year’s march drew more than 400,000 people, and this year’s turnout was “record-breaking,” said a spokeswoman for the organizers. Participants from California and Arizona, many Midwestern states, and all along the East Coast gathered under slate-gray skies that eventually gave way to light snow.

The event was peaceful and even lighthearted.

When the pro-lifers finally reached the Supreme Court, they were met by about 100 pro-choice supporters chanting “Ho, ho, hey, hey, Roe v. Wade is here to stay.” The young pro-life supporters surrounded their opponents and counterchanted, “Hey, hey, ho, ho, Roe v. Wade has got to go” before walking on.

The youthfulness of this year’s pro-life crowd impressed even veterans of this issue. The pro-life message is winning in the court of public opinion, in the states, and especially among the youth, said Jeanne Monahan, president of the March for Life Education and Defense Fund.

“Every year, it gets younger and younger, and the enthusiasm gets stronger and stronger,” said former Sen. Rick Santorum, a 2012 Republican presidential candidate and co-founder of Patriot Voices.

“I’m very, very hopeful,” Mr. Santorum said, standing with wife, Karen. “When you have a young person’s movement, the future is bright.”

“There’s a new generation rising,” said Tony Perkins, president of the Family Research Council. “I’m very optimistic. I think it’s a generation that’s searching, but I think it’s a generation that’s poised to choose life. So I think this is a turning point.”

Among the members of Congress who addressed the crowd were Republican Reps. Christopher H. Smith of New Jersey and Diane Black of Tennessee. Rep. Daniel Lipinski, Illinois Democrat, and House Speaker John A. Boehner, Ohio Republican, spoke by video.

Sen. Rand Paul, Kentucky Republican, electrified the crowd when he asked, “Can a nation long endure that doesn’t respect the sanctity of life?”

“I believe our country is in need of a revival” and “a spiritual cleansing,” Mr. Paul said. “As a physician, I have looked into the eyes of 1-pound babies. I have cradled their small bodies in the palm of one hand.

“I defy those who are careless, who would disregard life. I defy them to come to the neonatal nursery with me and look at these tiny little miracles and say, ‘We’re not going to protect that.’ “

The rally offered a video tribute to the founder of March for Life, Nellie Gray, who died in August at age 88.Gray was described as tenacious warrior, “one tough cookie” and “our Joan of Arc of the gospel of life.” The video included Gray speaking into the camera. “Believe me,” she said, “we are going to overturn Roe v. Wade.”